Guys, this is not a bug. For now, if you made your site private, the only way to make the custom page to be available to guests is to add the exception like it was done for Terms of Use, Privacy Policy and Contact us pages. Please check the /ow_core/application.php file to see how it works for the Terms of Use page.
Here is the function:
if ( UTIL_String::removeFirstAndLastSlashes($value->getUri()) == 'terms-of-use' )
{
OW::getRequestHandler()->addCatchAllRequestsExclude('base.members_only', $staticPageDispatchAttrs['controller'], $staticPageDispatchAttrs['action'], array('documentKey' => $value->getKey()));
}
}